Nail extracting device

ABSTRACT

A nail extracting device including a housing having a pair of handles to permit the user thereof to manipulate the device. The housing has a generally cylindrically shaped power section with a tubular extension of a rectangular cross section extending from one end thereof. A piston reciprocally mounted within the cylindrical power section is responsive to fluid pressure selectively communicated to the opposite sides of the piston to drive the same to and away from the tubular extension. The wall of the piston facing the tubular extension carries the inner end of an impact member which extends from the power section into the tubular extension where it is adapted to drivingly engage a pair of pivotally mounted nail engaging jaws. The impact member and the jaws are so arranged that movement of the piston toward the tubular extension drives the nail engaging jaws toward an outer opening in the tubular extension into a clamping engagement with the head of an embedded nail. Movement of the piston away from the tubular extension withdraws the jaws into the tubular extension and permits withdrawal of the nail from the material in which it is embedded. The piston has therewithin a percussion producing device operable to engage the inner end of the impact member to drive the jaws into the material to permit the jaws to clampingly engage the head of the embedded nail after the piston has driven the jaws toward the material. Valving means forming a part of the device are adapted to be manipulated by the operator of the device to selectively direct fluid pressure to the opposite sides of the piston to commence movement of the piston in the desired direction. The percussion producing device is automatically operable to drive the jaws into the material after the piston has moved the jaws toward the material for engagement with the embedded nail.

United States Patent [191 Ellis et al.

[ July 17, 1973 NAIL EXTRACTING DEVICE [75] inventors: Rollo G. Ellis, Charlotte, N.C.; Allan V. Ditty, Detroit, Mich.

[73] Assignee: Gerald T. Gilleran, Detroit, Mich.

a part interest [22] Filed: Feb. 16, 1972 [21] Appl. No.: 226,772

Related U.S. Application Data [63] Continuation-in-part of Ser'. No. 885,042, Dec. 15,

1969, Pat. No. 3,643,918.

Primary Examiner--Otheii M. Simpson Att0rneyAndrew R. Basile ['57] ABSTRACT A nail extracting device including a housing having a pair of handles to permit the user thereof to manipulate the device. The housing has a generally cylindricaliy shaped power section with a tubular extension of a rectangular cross section extending from one end thereof. A piston reciprocally mounted within the cylindrical power section is responsive to fluid pressure selectively communicated to the opposite sides of the piston to drive the same to and away from the tubular extension. The wall of the piston facing the tubular extension carries the inner end of an impact member which extends from the power section into the tubular extension where it is adapted to drivingiy engage a pair of pivotally mounted nail engaging jaws. The impact member and the jaws are so arranged that movement of the piston toward the tubular extension drives the nail engaging jaws toward an outer opening in the tubular extension into a clamping engagement with the head of an embedded nail. Movement of the piston away from the tubular extension withdraws the jaws into the tubular extension and permits withdrawal of the nail from the material in which it is embedded. The piston has therewithin a percussion producing device operable to engage the inner end of the impact member to drive the jaws into the material to permit the jaws to clampingly engage the head of the embedded nail after the piston has driven the jaws toward the material. Valving means forming a part of the device are adapted to be manipulated by the operator of the device to selectively direct fluid pressure to the opposite sides of the piston to commence movement of the piston in the desired direction. The percussion producing device is automatically operable to drive the jaws into the material after the piston has moved the jaws toward the material for engagement with the embedded nail.

22 Claims, 3 Drawing Figures United States Patent 1 [1 1 3,746,306 Ellis et al. 1 July 17, 1973 PATENTEU JUL 1 news sum 2 or 2 I NAIL EXTRACTING DEVICE CROSS REFERENCE TO RELATED PATENT APPLICATION The present patent application is a continuation-inpart of copending U. S. Pat. application Ser. No. 885,042 filed Dec. 15, I969 now Pat. No. 3,643,918.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in nail extracting devices and is particularly applicable to those of the type which are pneumatically operated.

2. Description of the Prior Art Heretofore various mechanical and power operated types of nail extracting devices have been devised and have included as their source of power electrical motors or hydraulic or pneumatic power means.

Nail extracting devices having electric motors as a source of power are characterized by several disadvantages such as the weight of the electric motor and the expense of their manufacture as they require special gearing in order to actuate the nail extracting mechanism. Hydraulic and pneumatic type power means which have been previously used to actuate nail extracting mechanisms have been very complicated in their manufacture requireing numerous cooperating components and have been generally designed for heavy duty applications such as removing spikes from railroad ties and the like and thus are very heavy and difficult to manipulate and are not adaptable fur use by an individual where a relatively lightweight nail extracting device is desired and necessary.

Further, many of the previously developed nail extracting devices have not included means for effectively driving the nail engaging jaws of the device into the material surrounding the nail head and have been intended for use only in withdrawing spikes in which the head is projected above the surface of the material from which they are to be extracted.

Lightweight, pneumatically operated devices adapted to have the nail engaging mechanism driven into the material surrounding the nail head to extract the nail have been previously developed, and, some of these to a great extent, overcome many of the disadvantages of the heretofore mentioned devices. However, these devices require numerous parts including complicated hydraulic or pneumatic systems, and due to the complexity of their construction are generally expensive in their manufacture, and thus are commercially impractical.

It is therefore desirable to provide a device operable to remove nails, spikes or the like from the material from which said nails or spikes are embedded. Such a device should be constructed in -a lightweight, simple, and inexpensive fashion adaptable for a variety of uses, and particularly for the unpackagin'g of materialsboxed in wooden or similar containers.

SUMMARY OF THE INVENTION The present invention which will be described subsequently in greater detail comprises a device operable to remove nails, spikes or the like from any material within which said nails or the like may bc 'driven. The device has'a pressure fluid operated impact member drivingly engaging a pair of pivotally mounted jaws and adapted to reciprocate the jaws between a first position in which the jaws are pivoted relative to one another to engage the head of the nail and a second position in which the jaws extract the nail from the material. The

impact member is reciprocally driven by a piston having therewithin a percussion producing means operable to engage the impact member when the same is in the first position so as to drive the jaws into the material into a clamping engagement with the nail to be extracted.

The simple construction of the present invention represents an improvement over prevously used nail extracting devices in that it is extremely simple and relatively inexpensive to construct and maintain.

It is therefore an object of the present invention to provide an improved nail extracting device which obviates the shortcomings and inaccuracies of previously used nail extracting devices.

Other objects, advantages and applications of the present invention will become apparent to those skilled in the art of nail extracting'devices when the accompanying description of one example of the best mode contemplated of practicing the invention is read in conjunction with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS The description makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and in which:

FIG. 1 is a longitudinal cross sectional view of a nail extracting device constructed in accordance with the principle of the present invention;

FIG. 2 is a fragmentary exploded perspective view of the nail extracting device illustrated in FIG. I; and

FIG. 3 is an end view of the nail extracting device as seen from line 3-3 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings and particularly FIGS. 1 and 2, there is illustrated a pneumatically operated nail extracting device 10 adapted to engage the head of 'a nail ll embedded in material 13 for the purpose of extracting the nail l1 therefrom.

Although the device 10 is illustrated as being pneumatically operated, it is to be understood that the invention is not restricted to such operation, and that other fluid mediums, such as hydraulic fluids may be utilized to provide the motor force for actuating the device 10.

The nail extracting device 10 comprises a housing 12 having a power section 14, a percussion producing section 15, and a tubular extension 16. The housing 14 has a pair of diametrically opposed handles 18 and 20 to provide the user of the device 10 with a means for supbore 22 within which is mounted a main piston 24 adapted to slidably engage the inner periphery of the bore 22 and reciprocate therewithin response to fluid pressure communicated to the opposite side walls .21 and 23 of mainpiston 24. The main piston 24 divides the bore 22 into two pressure chambers 26 and 28, re-

spectively, above and below the main piston 24 as viewed in FIG. 1. O-ring type seals 29 placed about the outer periphery of main piston 24 slidably engage the surface of the bore 22 to prevent fluid communication between the pressure chambers 26 and 28 and an annular recess 25 formed on the outer periphery of the main piston 24 as the recess 25 is constantly vented to atmosphere through a bore 27 extending through the wall of the housing 12. By slectively communicating fluid to either of the pressure chambers 26 or 28, the piston 24 will be reciprocated within the bore 22 in a manner to be described in greater detail hereinafter.

The tubular extension 16 is of generally rectangular shape having a radially enlarged cylindrical end section 32 received within the open end of the longitudinal bore 22 wherein an annular flange 33 radially extending from the enlarged end 32 abuts the exterior surface of the housing 12. The enlarged end 32 of the tubular extension 16 is securely retained to the power section 14 by means of a retainer ring 34 (FIGS. 3 and 9) which has an internal recess 35 engaging the outer periphery of the flange 33. Bolts 36 extend through a plurality of annularly spaced apertures to engage axially aligned threaded bores 37 (FIG. 2) within the housing 12.

The tubular extension 16 consists of a base 38 formed integrally with the enlarged end 32, and a cover plate 40 which is joined to the base 38 by a plurality of screws 41 only one of which is shown in FIG. 3. The cover plate 40 and the base 38 form a longitudinal guide bore 39 of a generally rectangular cross section in which a pair of guide plates 42 are removably mounted by means of nut and bolt assemblies 45. A pair of nail engaging jaws 44 and 46 are mounted for reciprocal movement on the guide plates 52 and within the guide bore 39 in a manner which will be described in greater detail hereinafter. The tubular extension guide bore 39 has an opening 47 adjacent at the bottom end 49 of the tubular extension 16 and is adapted to abut the surface of the material 13 in which the nail 11 is embedded. The bottom end 49 has a heel portion 61 integrally formed on the base 38 for a purpose to be described.

Each of the jaws 44 and 46 have teeth 48 at their lower extremity and an impact surface 50 immediately above their midsection and between their upper extremities. The midsection of each of the jaws 44 and 46 has a boss 52 in which a pintle bearing 54 is disposed to join the jaws 44 and 46 for pivotal movement about the axis of the pintle bearing 54. A lubricate saturated medium 55 disposed 'with a transverse bore 57 within the pintle bearing 54 provides proper lubrucation thereof. A wire spring 59 carried around the pintle bearing 54 and between the opposing faces 58 and 60 respectively of the jaws 44 and 46 exerts an outwardly directed force on the jaws 44 and 46 to pivot the jaws about the pintle bearing 54 for the purpose of spreading teeth 48 apart.

The pivotally attached jaws 44 and 46 form between their upper extremities a truncated shaped recess 62 having opposing inner surfaces 64 and 66 which are inclined with respect to the longitudinal axis of the tubular extension guide bore 39.'

The jaws 44 and 46 are adapted for reciprocal movement within the tubular extension guide bore 39 toward and away from the opening 47 by means of an impact member 70 which connects the jaws 44 and. 46 to the piston member 24. The impact member is an elongated cylindrically shaped rod slidably mounted in an axial bore 71 extending through the enlarged end 32 of the tubular extension 16 and a step bore 72 in the piston member 24. The inner end 73 of the impact member 70 has a radially enlarged flange 74 disposed within the bore 72 and is adapted to be engaged by a ring plate 75 mounted in the bore 72 when the piston member 24 is reciprocated toward the upper end of the housing bore 22 whereby thepiston member 22 will be operative to drive the impact member 70 upwardly therewith. As will be explained hereinafter in greater detail, the impact member 70 is adapted by movement in the bore 72 for a limited distance with respect to the piston member 24.

Suitable sealing means 76 and 77 respectively carried in recess 78 and 79 within the tubular extension bore 71 and the piston member bore 72 prevent fluid leakage from the pressure chamber 28 into the tubular extension guide bore 39 and the piston member bore 72.

The other end of the impact member 70 has a truncated flange 82 disposed within the truncated recess 62 of the jaws 44 and 46. The bottom of the impact member flange 82 defines an impact surface 88 adapted to engage the impact surfaces 50 formed above the midsection of the jaws 44 and 46 to provide the connecting means for driving the jaws toward the opening 47 as the piston member24 traverses from top to bottom, as viewed in FIG. 1, in response to fluid pressure being selectively directed to the pressure chamber 26.

The truncated flange 82 has a pair of opposing surfaces 90 and 91 which respectively engage the opposing surfaces 64 and 66 of the jaws during the upward stroke of the piston member 24 to thereby provide a second driving connection between the jaws and the impact member 70 as will be explained in greater detail hereinafter. As can best be seen in FIGS. 1 and 2, the percussion producing section 15 is mounted in the piston member bore 72 in axially alignment with the impactmember 70 adjacent the inner most end 73 thereof. The percussion producing section 15 comprises a second ri'ng plate 96 fixedly mounted in the step bore 72 and having a bore 98 through which the inner end 73 of the impact member is received. Movement of .the impact member 70 into the bore 98 is limited by the engagement of the radially enlarged flange 74 with the ring plate 96. When the pressure chamber 26 is pressurized to cause the piston member 24 to reciprocate toward the lower end of the housing bore 22, the engagement of the ring plate 96 with the flange 72 will result in the impact member being driven by the piston member 24. It can also be seen that the impact member is adapted for limited movement with respect to the piston member within the space between the two ring plates 75 and 96.

The percussion producing section 15 further comprises a sleeve member 100 mounted in the step bore 72 of the piston member 24 and having an axial bore 102 aligned with the impact member 70. The sleeve member 100 has spaced radially extending bore 104 and 106 which communicate the sleeve axial bore 102 with a peripheral recess 108, which in turn communicates with the piston member recess ZSthrough bores 109 in the wall of the piston member 24 and since the piston member recess 25 is constantly vented through housing bore 27, the sleeve bores 104 and 106 are constantly vented to atmosphere.

The sleeve member axial bore 102 slidably mounts a percussion piston 110 which divides the bore 102 into expansible pressure chambers 112 and 114 which when alternately communicated to fluid pressure cause the percussion piston 110 to reciprocate. On the down strike of the percussion piston 110, the end thereof forcefully engages the inner end 73 of impact member 70 to drive the same downwardly and thus drive the jaw teeth 48 into the material 13 as will be explained hereinafter. Fluid pressure is alternately communicated from the housing pressure chamber 26 to the sleeve member pressure chambers 112 and 114 respectively through internal passages 116 and 118 and an automatically operable valve mechanism 120. The valve mechanism 120 comprises an inner porting plate 122 having ports 124 and 126 respectively communicating with passages 116 and 118 and ports 130 and 132 in an outer cup shaped porting plate 134 while the ports 130 and 132 both constantly communicate directly with the housing pressure chamber 26 through a bore 136 in a retainer ring 138 secured to the piston 24 by screws 139. Communication between the ports 124 and 130, and 126 and 132 is alternately controlled by a tapered flapper valve 140 which is movable between a first position as illustrate in FIG. 1 wherein communication is opened between the ports 124 and 130 while communication between the ports 126 and 132 is closed. When the flapper valve 140 is rotated slightly counterclockwise as viewed in FIG. 1, communication between the ports 124 and 130 is closed while communication between ports 126 and 132 is opened.

When the flapper valve 140 is in the position shown in FIG. 1, pressure fluid from the housing chamber 26 enters the sleeve member pressure chamber 114 via ports 124, 130 and passage 118 and generates a force on the percussion piston 110 to drive the same into a forcefull engagement with the inner end 73 of the impact member 70. When the piston 110 moves past the vent port 106, the pressure chamber 1 14 is vented with the resulting pressure drop therein being reflected in a pressure differential across the flapper valve 140 causing the same to rotate counterclockwise closing off communication between the ports 124 and 130 while opening communication between the ports 126 and 132 and thus between the passage 116 and the housing pressure chamber 26. After the piston l has engaged the inner end 73 of the impact member 70, the piston 110 will bounce back up into the sleeve member bore 102 and open communication between the sleeve member pressure chamber 112 and the passage 116 with the pressure acting against the percussion piston 110 to drive it away from the impact member 70. As the piston 110 moves past the vent bore 104, the sleeve pressure chamber 112 will be vented immediately causing a pressure differential across the flapper valve 140 at the port 126 and 132 resulting in the valve 140 being rotated clockwise closing off further communication therethrough while opening fluid communication between the sleeve member pressure chanber 114 and the housing pressure chamber 26 via ports 124 and 130 wherein the reciprocating cycle of the percussion piston 110 is repeated and which will continue as long as the housing pressure chamber 26 is in communication with a source of fluid pressure as will be explained.

The activating fluid medium may take the form of any suitable pressurized fluid, however pressurized air is preferred. The pressurized air is communicated to ,the device 10 by any suitable air hose (not shown) having a suitable nozzle coupling which readily engages an inlet port of the device 10. Pressurized air entering the device 10 is directed through a passageway 152 to a valving mechanism 154 adapted to selectively direct fluid pressure to a passageway 156 or a passageway 158 which, in turn, are respectively connected to the pressure chambers 28 and 26 on opposite sides of the piston member 24. When fluid is directed to the pressure chamber 28, the piston member 24 is moved by the force of the fluid pressure acting on wall 23 in a direction away from the opening 47, that is, in an upward direction as viewed in FIG. 1. When fluid is directed to the pressure chamber 26, the piston member 24 is moved toward the opening 47 by the force of the fluid acting against the piston wall 21, that is, in a downward direction, as viewed in FIG. 1. Since the jaws 44 and 46 are drivingly connected to the piston member 24 by means of the impact member 70, the jaws 44 and 46 will reciprocate in the same manner as the piston member 24.

The valving mechanism 154 comprises a valve sleeve 160 fixedly positioned within a longitudinal blind bore 161 extending through the handle 18. The sleeve 160 is provided with a plurality of axially spaced ports 162, 164 and 166, each of which respectively communicate with annular recesses 168, and 172 extending around the outer periphery of the sleeve 160. The annular recesses 168, 170 and 172 are respectively in fluid communication with passageways 156, 152 and 158. Each of the recesses 168-172 are axially separated by a plurality of O-rings 174 suitably carried around the outer periphery of the sleeve 160 and adapted to engage the inner periphery of the bore 161 to prevent fluid communication between the several annular recesses. The ports 162, 164 and 166 communicate with a longitudinal bore 176 which extends through the sleeve 160 and in which a spool 178 is reciprocally mounted. Spool 178 has a pair of radially enlarged lands 180 and 184, each of which is provided with an O-ring 186 adapted to engage the inner peripheral surface of the bore 176 to prevent fluid communication between the opposite sides of the lands 180 and 184.

The lower end of the spool 178 has an enlarged portion which forms a trigger 188 in which the user of the device 10 presses and depresses to selectively communicate pressure fluid to either of the pressure chambers 26 or 28 as will be explained in greater detail hereinafter. The opposite end of the spool 178 has a stop plate 190 attached thereto by means of a threaded bolt 192. A portion of the inner surface of the stop plate 190 abuts the inner right end of the spool sleeve 160 to limit the downwardly or outward axial movement of the spool 178 which in turn, is biased in a downwardly or outward direction by a spring 194 disposed between the upper end of the stop plate 190 and the inner end of the blind bore 161. The inner surface of the stop plate 190 has a plurality of annularly spaced grooves (unnumbered) which are adapted to constantly connect the spool bore 178 to an exhaust bore 198 to vent pressurized air from the pressure chamber 26 when the trigger 188 is released as will be further described hereinafter.

During normal operation of the valve mechanism 154, the spring 194 biases the spool 178 such that fluid communication between the ports 162 and 164 is maintained to continuously direct fluid pressure from the air hose to the pressure chamber 28 and thereby bias the piston member 24 toward the upper wall of the housing bore 22.

To commence operation of the device 10 to drive the piston member 24 in a downwardly direction and thus drive the jaws 44 and 46 toward the surface of the material 13, the operator of the device 10 presses the trigger 188 inwardly. The inward movement of the trigger 188 displaces the spool 178 until the land 180 closes fluid communication between the ports 162 and 164 while the land 184 opens communication between the ports 164 and 166, thereby directing fluid pressure from the air hose to the pressure chamber 26. The pressure fluid communicated to the pressure chamber 26 exerts a force against the piston member wall 21 to urge the same in a downwardly direction toward the opening 47.

At the same time the air within the pressure chamber 28 is exhausted therefrom, by the downward movement of the piston member 24, into the exial passageway 156 and is exhausted externally of the device 10 via the valving mechanism 154. When the jaws 44 and 46 have engaged the nail, in a manner to be described hereinafter, the operator of the device releases the trigger 188 which, in turn closes communication between the port 164 and the port 166, while at the same time redirecting fluid pressure from the port 164 to the port 162 which in turn directs fluid pressure to the pressure chamber 28 to thereby exert a force against the fall 23 of the piston member 24 to urge the same in an upwardly direction. The upward movement of the piston member 24 forces the fluid within the pressure chamber 26 into the passageway 158 whereupon it is exhausted from the device 10 through the spool bore and the exhaust bore 198 and the piston member 24 returns vto the upper end of the housing bore 22.

In operation the user of the device 10 presses the trigger 188 to commence the downward movement of the piston member 24 whereupon the ring plate 96 of the piston member 24 engages the impact member flange 74 to drive the same downwardly. The impact surface 88 form on the truncated flange 82 abuts the impact surface 50 of jaws 44 and 46 to drive the same in the direction of the wooden member 13, whereby the teeth 48 are driven into the surface 51 of the wooden member 13.

in order to insure that the teeth 48 engage the underside of the head of the nail 11 in a clamping engagement to produce a proper withdrawalof the nail from the wooden member 13, the guide plates 42 each have an inclined cam surface 200 proximate the opening 47. The outer walls of each jaws 44 and 46 at thelower extremities engage the cam surfaces 200 to cam the teeth 48 inwardly towards the head of the nail 1 1 at the same time the teeth are penetrating the wooden member 13, thus insuring the teeth 48 engage the underside of the head of the nail 11.

In order to insure that the head of the nail 1 1 and the teeth 48-of the jaws 44 and 48 are properly aligned so as to clampingly engage the teeth 48 with the nail 11 upon actuation of the device 10 a portion of the cover and base are provided with a slot 202 (FIG. 3) which extends from the opening 47 upwardly along one side to about the mid section of the tubular extension 16. The slot 202 permits the visual alignment of the device 10 by the user to insure proper operation thereof once the device 10 is actuated.

After the piston member 24 has driven the jaws to the material 13 and while the housing pressure chamber 26 is still pressurized, the percussion producing device 15 will function as herebefore described to effect a further hammering of the jaw teeth 48 into the material 13 to insure that the jaw teeth 48 have clampingly engaged the nail head.

After the teeth 48 of the jaws have engaged the underside of the head of the nail 11, the operator of the device 10 depresses the trigger 188 and thereby directs fluid pressure into the pressure chamber 28 to exert a force against the piston member wall 23 so that the same is displaced in an upward direction away from the openings 47 as hereinbefore described. As the piston member 24 travels in an upward direction, the opposing surfaces and 91 of the truncated flange 82 respectively engage the inclined surfaces 64 and 66 on the inner walls of jaws 44 and 46 and thereby exert an upwardly directed force against the jaws to pull them away from the wooden member 13. Simultaneously with the upwardly directed force, the engaging inclined surface exerts an outwardly directed force against the upper extremities of the jaws 44 and 46. Such an outwardly directed force tends to spread the upper extremities of the jaws 44 and 46 thereby tending to maintain the teeth 48 in a clamping engagement about the head of the nail 11 while the nail 11 is being extracted from the wooden member 13. As the piston member 24 travels along the bore 22 to the inner end of the power section 14, the nail is withdrawn from the wooden member 13. The lower surface 47 of the device 10 is in abutment with the surface of the wooden member 13 whereby the force of removing the nail is transferred back to the wooden member, and the user need exert only enough force and control upon the device 10 to maintain it in an upright position with respect to the wooden member 13. If the nail 11 is not easily extracted from the material 13 after the trigger 188 is released, the user may grasp the upper handle 21 and tip the device 10 on the heel portion 61 to provide an additional leverage to aid in the removal of the nail 11.

After the nail 11 is withdrawn from the material 13, the force of the spring 59 acting against the lower extremities of the jaws tends to separate them and release the nails from between the teeth 48, while the piston member 24 continues to move to the upper end of the its stroke in the manner hereinbefore described.

In order to minimize the weight in the overall assembly of the nail extracting device 10, the components may be made from a lightweight material such as aluminum or aluminum alloys. Such materials are sutiable for forming the piston member 24 and the housing 12. However those components which sustain impact and hard usage, such as the impact member 70, the percussion producing section 15, the jaws 44 and 46 and, par ticularly, the teeth of the jaws 44 and 46 should be formed from a suitable material such as tempered steel, all of which is well known in the art of metallurgy.

It can thus be seen that the present invention has provided a new extracting device which is extremely simple in construction, which is capable of being made of relatively lightweight materials and'so designed that the same can be maintained and repaired in a simple and less expensive manner as compared to other perviously mentioned extracting devices capable of performing similar functions.

Although only one embodiment of the present invention has been disclosed, it is to be understood by those skilled in the art of nail extracting devices that other forms can be made, all coming within the spirit of the invention and the scope of the appended claims.

We claim:

1. A nail extracting device for removing a nail from a material, said device comprising:

a housing having a longitudinal bore;

piston means reciprocally mounted in said housing bore; an impact member carried at one end thereof by said piston means and reciprocal therewith, said one end of said impact member being independently movable a limited distance with respect to said piston means; nail engaging jaw means carried at the other end of said impact member, said impact member being reciprocally driven by said piston means toward said material containing said nail to drive said jaw means into said material and after said jaw means engages said nail to withdraw said jaw means away from said material to extract said nail therefrom;

reciprocating percussion producing means carried within said piston and movable therewith, said percussion producing means being automatically operable to drivingly engage said one end of said impact member to move same said limited distance with respect to said piston means after said piston means has driven said impact member towards said material so as to drive said jaw means into said material and cause engagement with said nail; and

means for selectively reciprocating said piston means.

2. The nail extracting device defined in claim 1 wherein the piston means comprises a piston slidably mounted in said housing bore, the opposite ends of said piston defining the movable walls of a pair of pressure chambers, said impact member one end being carried by one of said walls, said piston being driven away from said material when the one pressure chamber associated with said one wall is exposed to a pressure fluid while said piston is driven toward said material when the other pressure chamber associated with the other wall is exposed to pressure fluid; and means for selectively communicating pressure fluid to said pressure chambers.

3. The nail extracting device defined in claim 2 wherein said percussion producing means becomes operable when said other pressure chamber is exposed to pressure fluid and sad piston has moved toward said material. I

4. The nail extracting device defined in claim 2 wherein said piston has a longitudinal bore, said one end of said impact member being received in said piston bore; said percussion producing means comprises a second piston reciprocally mounted in said piston bore and dividing said piston bore into two piston pressure chambers which when alternately communicated to pressure fluid cause said second piston to reciprocate, said reciprocating second piston engaging said one end of said impact member to move same said limited distance; and means for alternately communicating said piston pressure chambers to pressure fluid.

5. The nail extracting device defined in claim 4 wherein said last mentioned means is operable when said other housing pressure chamber is exposed to pressure fluid.

6. The nail extracting device defined in claim 4 further comprising a valve adapted to open communication between said other housing pressure chamber and one of said piston pressure chambers while closing communication between said other housing pressure chamber and the other of said piston pressure chambers, means venting said one piston pressure chamber after said second piston has moved in one direction a predetermined distance, said vented piston pressure chamber being operable to cause said valve means to close communication between same and said other housing pressure chamber while opening communication between said other housing pressure chamber and said other piston pressure chamber thereby causing said second piston to move a predetermined distance in an opposite direction.

7. The nail extracting device defined in claim 4 wherein said first mentioned piston, said second piston, said impact member and said jaw member reciprocate along a common axis.

8. The nail extracting device defined in claim 6 wherein said first mentioned piston and said second piston are pneumatically operated.

9. The nail extracting device defined in claim 1 wherein said jaw means comprise a pair of pivotally mounted nail engaging jaws reciprocally driven by said impact member, the other end of said impact member being positioned between the upper extremitiesof said pivotally mounted jaws said other end of said impact member having at least two jaw engaging surfaces, said impact member being adapted for limited movement independently of said jaws between first and second positions wherein after movement of said impact member to said first position one of said jaw engaging surfaces engages said jaws to drive the lower extremities of said jaws into said material as said percussion producing means drivingly engages the one end of said impact member; camming means disposed at the lower extremities of said jaws and cooperating with said housing for pivoting said jaws relative to one another to close the lower extremities thereof into a clamping engagement with said nail as said jaws are driven by said impact member into said material, and wherein after movement of said impact member to said second position, the other of said jaw engaging surfaces of said impact member engages said jaws to urge the upper extremities of said jaws to separate thereby maintaining said lower extremities of said jaws in said clamping engagement with said nail while simultaneously said othere jaw engaging surface drives said jaws away from said material as said impact member moves in a direction away from said material to effect extraction of said nail therefrom.

10. The nail extracting device defined in claim 9, wherein said impact member is a rod having an enlarged other end, said other surface being disposed thereon and inclined with respect to the direction of reciprocal movement of said rod, said jaws having opposing inclined surfaces approximate their upper extremities at a point above the pivotal axis of said jaws, said opposing inclined surfaces being engaged by said rod inclined surfaces to spread said upper extremities of said jaws.

11. The nail extracting device defined in claim 10, wherein said other end of said rod connecting said inclined other surfaces is adapted to engage said jaws between said jaw opposing inclined surfaces and above said pivotal axis to drive said jaws into engagement with said material.

12. The nail extracting device defined in claim including resilient means carried by said jaws for biasing the lower extremities apart.

13. in a nail extracting device defined in claim 10 wherein said resilient means comprises a spring exerting an outwardly directed force between the opposite inner walls of said jaws at a point below said pivotal axis, said spring being a wire spring corried around said pivotal axis.

14. The nail extracting device defined in claim 9, wherein said housing further comprises a tubular member having a material abutting end surface, said jaws being mounted in said tubular member for reciprocal movement in response to said impact member.

15. The nail extracting device defined in claim 14 wherein a portion of the inner walls of said tubular member cooperates with a portion of the outer walls of said jaws to guide said jaws as the same travel within said tubular member.

16. The nail extracting device defined in claim 15, wherein a pair of opposing inner walls of said tubular member are shaped complementary to the cooperating wall portions of said jaws such that said jaw portions slidably engage said opposing inner walls of said tubular member.

17. The nail extracting device defined in claim l4,

wherein said camming means comprising a cam surface disposed on said tubular member approximate said material abutting surface, said cam surface being inclined with respect to the direction of movement of said jaws, said cam surface engaging the lower extremities of said jaws to urge said jaws into a clamping engagement with said nail.

18. The nail extracting device of claim 14 including a longitudinal slot extending upwardly from said material abutting surface and through a portion of said tubular wall to provide the user of said nail extracting device with a view of said jaws to permit proper axial alignment thereof with the nail to be extracted from said material.

19. The nail extracting defice defined in claim 9 wherein said piston means is pneumatically operated.

20. The nail extracting device defined in claim 14 wherein said tubular member is carried at one end by said housing and has a radially extending flange in abutment with said housing, a retainer surrounding said tubular extension and engaging said flange to securely retain said tubular extension to said housing; and means fastening said retainer to said housing.

21. The nail extracting device defined in claim 17 wherein said cam surface is removably fastened to said tubular member. '5

22. The nail extracting device defined in claim 14 further comprising a lever means carried proximate said material abutting end surface to permit tipping of said device to aid in the extraction of said nail from said material.

* a: a: a: 

1. A nail extracting device for removing a nail from a material, said device comprising: a housing having a longitudinal bore; piston means reciprocally mounted in said housing bore; an impact member carried at one end thereof by said piston means and reciprocal therewith, said one end of said impact member being independently movable a limited distance with respect to said piston means; nail engaging jaw means carried at the other end of said impact member, said impact member being reciprocally driven by said piston means toward said material containing said nail to drive said jaw means into said material and after said jaw means engages said nail to withdraw said jaw means away from said material to extract said nail therefrom; reciprocating percussion producing means carried within said piston and movable therewith, said percussion producing means being automatically operable to drivingly engage said one end of said impact member to move same said limited distance with respect to said piston means after said piston means has driven said impact member towards said material so as to drive said jaw means into said material and cause engagement with said nail; and means for selectively reciprocating said piston means.
 2. The nail extracting device defined in claim 1 wherein the piston means comprises a piston slidably mounted in said housing bore, the opposite ends of said piston defining the movable walls of a pair of pressure chambers, said impact member one end being carried by one of said walls, said piston being driven away from said material when the one pressure chamber associated with said one wall is exposed to a pressure fluid while said piston is driven toward said material when the other pressure chamber associated with the other wall is exposed to pressure fluid; and means for selectively communicating pressure fluid to said pressure chambers.
 3. The nail extracting device defined in claim 2 wherein said percussion producing means becomes operable when said other pressure chamber is exposed to pressure fluid and sad piston has moved toward said material.
 4. The nail extracting device defined in claim 2 wherein said piston has a longitudinal bore, said one end of said impact membEr being received in said piston bore; said percussion producing means comprises a second piston reciprocally mounted in said piston bore and dividing said piston bore into two piston pressure chambers which when alternately communicated to pressure fluid cause said second piston to reciprocate, said reciprocating second piston engaging said one end of said impact member to move same said limited distance; and means for alternately communicating said piston pressure chambers to pressure fluid.
 5. The nail extracting device defined in claim 4 wherein said last mentioned means is operable when said other housing pressure chamber is exposed to pressure fluid.
 6. The nail extracting device defined in claim 4 further comprising a valve adapted to open communication between said other housing pressure chamber and one of said piston pressure chambers while closing communication between said other housing pressure chamber and the other of said piston pressure chambers, means venting said one piston pressure chamber after said second piston has moved in one direction a predetermined distance, said vented piston pressure chamber being operable to cause said valve means to close communication between same and said other housing pressure chamber while opening communication between said other housing pressure chamber and said other piston pressure chamber thereby causing said second piston to move a predetermined distance in an opposite direction.
 7. The nail extracting device defined in claim 4 wherein said first mentioned piston, said second piston, said impact member and said jaw member reciprocate along a common axis.
 8. The nail extracting device defined in claim 6 wherein said first mentioned piston and said second piston are pneumatically operated.
 9. The nail extracting device defined in claim 1 wherein said jaw means comprise a pair of pivotally mounted nail engaging jaws reciprocally driven by said impact member, the other end of said impact member being positioned between the upper extremities of said pivotally mounted jaws said other end of said impact member having at least two jaw engaging surfaces, said impact member being adapted for limited movement independently of said jaws between first and second positions wherein after movement of said impact member to said first position one of said jaw engaging surfaces engages said jaws to drive the lower extremities of said jaws into said material as said percussion producing means drivingly engages the one end of said impact member; camming means disposed at the lower extremities of said jaws and cooperating with said housing for pivoting said jaws relative to one another to close the lower extremities thereof into a clamping engagement with said nail as said jaws are driven by said impact member into said material, and wherein after movement of said impact member to said second position, the other of said jaw engaging surfaces of said impact member engages said jaws to urge the upper extremities of said jaws to separate thereby maintaining said lower extremities of said jaws in said clamping engagement with said nail while simultaneously said othere jaw engaging surface drives said jaws away from said material as said impact member moves in a direction away from said material to effect extraction of said nail therefrom.
 10. The nail extracting device defined in claim 9, wherein said impact member is a rod having an enlarged other end, said other surface being disposed thereon and inclined with respect to the direction of reciprocal movement of said rod, said jaws having opposing inclined surfaces approximate their upper extremities at a point above the pivotal axis of said jaws, said opposing inclined surfaces being engaged by said rod inclined surfaces to spread said upper extremities of said jaws.
 11. The nail extracting device defined in claim 10, wherein said other end of said rod connecting said inclined other surfaces is adapted to engage said jaws between said jaw opposing inclined surfaces and above said pivotal axis to drive said jaws into engagement with said material.
 12. The nail extracting device defined in claim 10 including resilient means carried by said jaws for biasing the lower extremities apart.
 13. In a nail extracting device defined in claim 10 wherein said resilient means comprises a spring exerting an outwardly directed force between the opposite inner walls of said jaws at a point below said pivotal axis, said spring being a wire spring corried around said pivotal axis.
 14. The nail extracting device defined in claim 9, wherein said housing further comprises a tubular member having a material abutting end surface, said jaws being mounted in said tubular member for reciprocal movement in response to said impact member.
 15. The nail extracting device defined in claim 14 wherein a portion of the inner walls of said tubular member cooperates with a portion of the outer walls of said jaws to guide said jaws as the same travel within said tubular member.
 16. The nail extracting device defined in claim 15, wherein a pair of opposing inner walls of said tubular member are shaped complementary to the cooperating wall portions of said jaws such that said jaw portions slidably engage said opposing inner walls of said tubular member.
 17. The nail extracting device defined in claim 14, wherein said camming means comprising a cam surface disposed on said tubular member approximate said material abutting surface, said cam surface being inclined with respect to the direction of movement of said jaws, said cam surface engaging the lower extremities of said jaws to urge said jaws into a clamping engagement with said nail.
 18. The nail extracting device of claim 14 including a longitudinal slot extending upwardly from said material abutting surface and through a portion of said tubular wall to provide the user of said nail extracting device with a view of said jaws to permit proper axial alignment thereof with the nail to be extracted from said material.
 19. The nail extracting defice defined in claim 9 wherein said piston means is pneumatically operated.
 20. The nail extracting device defined in claim 14 wherein said tubular member is carried at one end by said housing and has a radially extending flange in abutment with said housing, a retainer surrounding said tubular extension and engaging said flange to securely retain said tubular extension to said housing; and means fastening said retainer to said housing.
 21. The nail extracting device defined in claim 17 wherein said cam surface is removably fastened to said tubular member.
 22. The nail extracting device defined in claim 14 further comprising a lever means carried proximate said material abutting end surface to permit tipping of said device to aid in the extraction of said nail from said material. 